Your internet connection is unstable

Test your Internet Connectivity
When the internet connection is slight chances of encountering an unstable Zoom connection are strong. To confirm whether this is the case, try to open the same website using an alternate device to check if there’s internet connectivity. If not, connect with your Internet service provider for assistance.

Fix 2 – Use the Network Troubleshooter
To auto-detect and fix problems encountered on Windows, there’s a built-in Troubleshoot provided. You can use it to resolve the wireless and other network adapters issues.

Press Windows + S and type troubleshoot > click Troubleshoot settings.
Click Additional troubleshooters.
Look for Network Adapter. Click on it and click Run the troubleshooter.

Regards,
James

Since a problem with the Zoom connection pretty clearly means a problem with internet connectivity, I used the troubleshooter first thing, moving on (as mentioned previously) to replacing all my equipment, including router and coax cable. No luck.

I have the same problem but with a macbook air. Have you tried a powerline adaptor? 

Hello! I upgraded my internet speed and router and also submitted a ticket for support from Zoom. Here's the reply I got. Hope this helps.

Step 1
 
What you need to do here is to open the Finder on your Mac. From Finder, click on Go on the top and from there, paste the directory which is ~/Library/Preferences/ZoomChat.plist
 
This will directly open the folder and you will see the file ZoomChat.plist in the folder.
 
Step 2
 
You can go ahead and delete the plist file from the folder. Please make sure you quit the Zoom Desktop application first before doing these steps. Once you are done with these steps, kindly go ahead and perform this solution.
 

1. Properly uninstall the desktop client by following the steps in the How to uninstall Zoom article
2. Install the latest version of the desktop client from https://zoom.us/download
3. Verify if you are installing the correct zoom client based on their mac chip model. We have standard clients and Macs with Apple Silicon chips.

 
I have attached a screenshot for your reference.
 
If you have any additional questions or concerns, feel free to reach us back or visit our help center page at support.zoom.us.

Like DM50, I have been experiencing this very irritating problem: poor quality video, video freeze, erratic delays when screen sharing, severe degradation of voice quality

Colleagues and customers have commented on the lag and the significant degradations in sound quality, particularly when screen sharing. It is so bad that it is affecting my sales.

The problem occurs entirely randomly on a call, even when I have switched off apps such as Miro and Fathom and am not recording on Zoom
In video settings, I have switched off optimise quality settings, as well as the use of hardware acceleration
I have followed the guidance to make adjustments to the video for IRIS graphics cards to use Direct3D9
My laptop is a 2023 highest-spec Lenovo Thinkpad with 32Gb of RAM. Neither the CPU, Memory utilisation, GPU are at anywhere near critical levels.
My connection is hardwired gigabit ethernet, so I am seeing stable speeds of 700Mbps up and down with 2ms delay.
I have set up to connect to local Zoom data centres in each geography that I call to
I have tested the presentations I am typically sharing with various versions: powerpoint, google slides, pdf. Same result

I have tested the same setup with both Around and Google Meet. video quality is perfect, no video freezing, instant rendition when sharing, voice quality is perfect

My conclusion: it is not me, or my machine, it is most definitely Zoom. If the service does not reach the quality one should reasonably expect, why should I pay for it?

I've been suffering a similar problem - freezing - but more significantly the zoom app crashing multiple times during a session.  Occasion message "internet connection unstable".   I switched over to my laptop on the same internet connection without the same problems so I don't believe the message - except to imagine that Zoom is having trouble within my desktop machine.   I've lots of internet experience and not seen this elsewhere.   I'm now trying the complete uninstall and clean of Zoom client and reinstalling.....  We'll see.  I suspect something within my desktop machine is interfering with the stability of the program.  It seems to happen more when I add another function in - the chat window, for example....

Was this ever solved? I have the same problem! I've upgraded my service to a faster speed, replaced the router and modem and I've had a technician out 3 times. Still I cannot go more than a few minutes without freezing or losing audio and video.

I have been working through this issue, including via a dialogue with a L2 technician at Zoom

I didn't realise you could look at the performance of the session
(Not in a call) Go to your picture on the application home page (top right)
Click on Settings, then Statistics
Then open a test call.
When you click on the various tabs: Overall | Audio | Video | Sharing  you can see what is happening
Then suggest you use NPerf before you open Zoom, when in the call generally, and when screen sharing, to see what happens. Typically, you might see packet losses in audio and / or video

Then you could test to see if a wired or a wireless connection makes any difference.
Finally, you could see whether using a mobile hotspot as your wireless connection makes any difference!
For me it does. My wired broadband connection runs at approaching 1GBps and the wireless speeds using the same broadband service are around 700Mbps, with around 4 ms latency on average. Yet the problems happen.

My mobile hotspot runs at less than 50Mbps up and down. NO LAG. NO FREEZING. NO JAGGY VOICE.
Only problem - I run video calls most of the day and my monthly data allowance is just 100Gb

I have checked with my internet security (Bitdefender) to see if there is something there causing the delay. Maybe open Task Manager when you are running a Zoom call, to see if there is any heavy processing going on that might be causing the delay.

After that, I will get in touch with my ISP. I will invite them to demonstrate the stability of their network provision

Thanks for reading. I hope there were some useful suggestions in there.

Dealing with the unstable internet messages and another issue – a beep audible to everyone on the Zoom whenever anyone enters or leaves the meeting – I was told to get a second monitor and access Zoom through the second monitor, and that has worked. I can't remember where but I think this came from extended discussions on a different Zoom Community forum.

I have found a solution for me at least. I did a ping to www.zoom.us and found I was losing packets. Then I did a ping to my router 192.168.1.1 and found I was losing packets there too! I unplugged a power-line that I had connected to the router and all the problems disappeared. Zoom worked! Something to do with the power-line is disrupting my home network. I will search more to find exactly what it is.